The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 01, 1992
Filed:
Jul. 26, 1990
Sheryl L Johnson, Sunnyvale, CA (US);
Bryan K Clark, Sunnyvale, CA (US);
Tandy Corporation, Fort Worth, TX (US);
Abstract
A method of achieving a bulk erasure of a dye polymer optical storage media which includes a substrate, an expansion layer, and a retention layer. The optical storage media is placed into a temperature controlled environment in which the temperature is increased at a first prescribed rate to a prescribed temperature exceeding the glass transition temperature of the retention layer of the media. Above the glass transition temperature, the retention layer is transformed from a glass-like state to a viscoelastic state. While in the viscoelastic state, the retention layer shape conforms to the expansion layer to achieve the unrecorded media configuration (i.e. flat). The temperature of the controlled environment is maintained at the prescribed temperature for a specified period of time to achieve the bulk erasure, then reduced at a second prescribed rate. By controlling the prescribed temperature and specified time period, the media is erased in bulk providing an unrecorded media ready for use. The prescribed temperature, specified time period and temperature change rates are selected to avoid thermal shock and polymer degradation and thus enable many record/erase transitions of the media.